scholarly journals Study on the Cooling Effect of Attached Fins on PV Using CFD Simulation

Energies ◽  
2019 ◽  
Vol 12 (4) ◽  
pp. 758 ◽  
Author(s):  
Jaemin Kim ◽  
Yujin Nam
Keyword(s):  
Simulation Model ◽  
Cfd Simulation ◽  
Hot Spot ◽  
Cooling Effect ◽  
Dynamics Simulation ◽  
Solar Simulator ◽  
Cooling Performance ◽  
Electrical Efficiency ◽  
Pv Module ◽  
Simulation Results

The issue of efficiency decrease according to temperature increase is a pending problem in the PV market. Several active and passive technologies have been suggested but few quantitative studies on the estimation of the cooling effect have been carried out. In this study, a CFD (computational fluid dynamics) simulation model was developed to analyze a passive cooling technology using fins attached to the back of the PV module. Furthermore, a method to improve airflow at the back of the PV module by forming slits in the frame was analyzed. The simulation model reproduced the indoor test that uses a solar simulator and the cooling performance was analyzed according to the shape of the fins and the presence of slits. In the simulation results, the surface temperature and expected electrical efficiency without cooling were 62.78 °C and 13.24% respectively under nominal operating cell temperature conditions. Moreover, the temperature reduced by approximately 15.13 °C because the fins attached at the bottom of the PV module increased the heat transfer area with airflow. Thus, the electrical efficiency according to the PV module temperature was predicted as 14.39%. Furthermore, when slits were installed between the fins, they increased the airflow velocity and accelerated the formation of turbulence, thereby improving the cooling performance of the fins. The simulation results showed that the temperature could be further reduced by approximately 8.62 °C at a lower air velocity. As the fins and slits can also reduce the non-uniformity of the temperature, they are expected to supplement the efficiency and durability reduction of the PV modules caused by the hot spot phenomenon. In addition, it was shown that slits in the frame could further improve the cooling performance of the fins at a low-velocity airflow.

scholarly journals Experimental and Numerical Study on the Cooling Performance of Fins and Metal Mesh Attached on a Photovoltaic Module

Energies ◽  
2019 ◽  
Vol 13 (1) ◽  
pp. 85 ◽  
Author(s):  
Jaemin Kim ◽  
Sangmu Bae ◽  
Yongdong Yu ◽  
Yujin Nam
Keyword(s):  
Cfd Simulation ◽  
Numerical Study ◽  
Experimental Studies ◽  
Photovoltaic Module ◽  
Metal Mesh ◽  
Solar Simulator ◽  
Cooling Performance ◽  
Electrical Efficiency ◽  
Pv Module ◽  
Pv Cooling

The electrical efficiency and durability of a photovoltaic (PV) cell degrades as its temperature increases. Accordingly, there have been continued efforts to control the cell temperature by cooling the PV module. Generally, passive PV cooling using heat sinks attached on the back of the PV module can improve the electrical efficiency. However, few experimental studies have evaluated the effect of the heat sink shape on PV cooling. Therefore, this study proposed a passive cooling technology using meshes made of iron and aluminum, and performed indoor tests using a solar simulator to analyze the cooling performance. The experimental results demonstrated that iron and aluminum meshes reduced the PV module temperature by approximately 4.35 °C and 6.56 °C, respectively. Additionally, numerical studies were performed using a computational fluid dynamics (CFD) simulation to compare the cooling fins and meshes. The numerical results showed that the cooling fins exhibited a better cooling performance than the metal mesh. However, meshes can be mass-produced and have a high structural stability against wind loads. Meshes are more likely be applied to PV systems than cooling fins if adhesion were improved.

Alpha Radioactivity Monitor Using Ionized Air Transport Technology for Large Size Uranium Waste: Part 2—Simulation Model Reinforcement for Practical Apparatus Design

2010 ◽  
Author(s):  
Takatoshi Asada ◽  
Yosuke Hirata ◽  
Susumu Naito ◽  
Mikio Izumi ◽  
Yukio Yoshimura
Keyword(s):  
Ion Transport ◽  
Simulation Model ◽  
Cfd Simulation ◽  
Transport Model ◽  
Model Simulation ◽  
Ion Density ◽  
Transport Simulation ◽  
Simulation Results ◽  
Alpha Radioactivity ◽  
Ionized Air

In alpha radioactivity measurement using ionized air transportation (AMAT), conversion from ion currents to radioactivity accurate is required. An ion transport simulation provides ways of complementarily determining conversion factors. We have developed an ion transport simulation model. Simulation results were compared with experiments with air speeds, faster than 1 m/s, achieving good agreement. In a practical AMAT apparatus, the air-flow at the alpha source may be slower than 1 m/s, and ion loss is likely to be large. Reinforcement of the ion transport model to cover the lower air speed region is effective. Ions are generated by an alpha particle in a very thin column. Since the ion density at this temporal stage is high, the recombination loss, proportional to the square of ion density, is dominant within a few milli-seconds. The spatial and temporal scales of this columnar recombination are too small for CFD simulation. We solve an ion transport equation during the period of columnar recombination with diffusion and recombination terms and incorporated the relation between ion loss and turbulent parameters into CFD. Using this model, simulations have been done for various air speeds and targets. Those for simulation results agree with experiments, showing improvement of simulation accuracy.

Kinematics and Dynamics Simulation of Feed Mechanism of Sewing Machine Based on SimMechanics

2013 ◽  
Vol 694-697 ◽  
pp. 31-35
Author(s):  
Xiao Zheng Dang ◽  
Liang Sheng Zhou ◽  
Bao Cheng Ding
Keyword(s):  
Stress State ◽  
Simulation Model ◽  
Textile Industry ◽  
Dynamics Simulation ◽  
Kinematics And Dynamics ◽  
Sewing Machine ◽  
Machine System ◽  
The Future ◽  
Simulation Results

Planner six-bar mechanism is widely used in the textile industry. In this article, feed mechanism of sewing machine is studied. The kinematics and dynamics simulation model is established for this kind of mechanism. On the basis of it, a relevant simulation is carried out through SimMechanics. Thus, the motion rules and stress state for all parts of mechanism are described vividly. The simulation results show that this method is effective and efficient when the simulation is implemented for a certain machine system. Meanwhile, it provides a foundation for the further research of the mechanism in the future.

Study on Impact of Powertrain Mounting Stiffness on Vehicle Vibration Characteristics

2012 ◽  
Vol 605-607 ◽  
pp. 1154-1157
Author(s):  
Yu Zhuo Men ◽  
Hai Bo Yu ◽  
Hua Wang ◽  
Liang Xu
Keyword(s):  
Simulation Model ◽  
Simulation Analysis ◽  
Drive Shaft ◽  
Dynamics Simulation ◽  
Interpolation Function ◽  
Vibration System ◽  
Nonlinear Characteristics ◽  
Model Reliability ◽  
Simulation Results ◽  
Stiffness And Damping

ADAMS was used to establish the dynamics simulation model of a truck vehicle vibration system, while the engine, drive shaft and tire excitations were added to the model. For nonlinear characteristics of rubber mounting components stiffness and damping, input was conducted by the use of interpolation function SPLINE. Through the comparison of road tests and simulation results, the model reliability was verified and simulation analysis was conducted on this basis. The results show that reasonable selection and matching of powertrain mounting stiffness, mounting position could effectively improve the performance of vehicle vibration system.

scholarly journals Multi-Scenario Simulation of a Water–Energy Coupling System Based on System Dynamics: A Case Study of Ningbo City

Energies ◽  
2021 ◽  
Vol 14 (18) ◽  
pp. 5854
Author(s):  
Yitong Yin ◽  
Gang Lin ◽  
Dong Jiang ◽  
Jingying Fu ◽  
Donglin Dong
Keyword(s):  
Water Resources ◽  
System Dynamics ◽  
Simulation Model ◽  
Energy Saving ◽  
Energy Coupling ◽  
Water Saving ◽  
Driving Factors ◽  
Dynamics Simulation ◽  
Coupling System ◽  
Simulation Results

In this work, based on the concept of collaborative water–energy development, a multi-scenario system dynamics simulation model of a water–energy coupling system was constructed by using the system dynamics modeling method. The model was composed of four subsystems: society, economic, water resources, and energy. Taking Ningbo City as the research location to run the simulation model, the analysis of the validity of the model showed that the relative error between the historical data and the simulation results of the model was less than 10%, which proved that the model passed the test. In this paper, based on the scenario of business an usual (BAU), three scenarios of water-saving scenario (WSS), energy-saving scenario (ESS), and comprehensive savings (CS, the comprehensive scenario considers water-saving and energy-saving together) were designed, and the simulation indexes in the three scenarios were refined in order to strengthen the control of water-saving policies, improve the effective use of water, optimize the industrial energy structure, improve the level of energy-saving-related technologies, and advance the urbanization process. The simulation results for Ningbo City from 2010 to 2030 show that the water–energy coupling system is affected by many factors, and the adjustment of a driving factor of any subsystem will have an impact on the water–energy coupling system. There are two driving factors: the first is a constant variable related to water resources, energy, society, and economic, and the second is a variable affected by time. The coupling system is based on the law of real development and is composed of causal and functional relationships between variables. Therefore, within the prediction range of 2030, the driving factors in the coupling system are controllable, and there is no uncontrollable situation. The strengthening of water-saving policies and the improvement of the coefficient of the effective utilization of water will have the optimal saving effects on water resources and energy at both the single and the coupling level; this also demonstrates that the water resource management in Ningbo City plays an extremely important role in the relationship of the water–energy coupling. The results of this study are expected to provide a valuable reference for the management and conservation of water–energy coupling in Ningbo City.

Sun Load Analysis and Testing on Automotive Front Lighting Products

2020 ◽  
pp. 116-122
Author(s):  
Emre Öztürk ◽  
Mehmet Aktaş ◽  
Tunç Şenyüz
Keyword(s):  
Prolonged Exposure ◽  
Hot Spot ◽  
Load Test ◽  
Angle Of Incidence ◽  
The Sun ◽  
Solar Simulator ◽  
Automotive Lighting ◽  
Inclination Angles ◽  
Plastic Parts ◽  
Load Simulation

The purpose of this research is to reach good correlation between sun load simulation and solar focusing test for exterior automotive lighting products. Light coming from sun is highly collimated (parallel rays) and focusable from lenses with concave structure. Focusing incidence leads to a hot spot on lens surrounding plastic parts which may cause melting failures at high temperature zones. Sun load simulation is performing to eliminate risk of discoloration, deformation, out gassing, coating failures and fire with prolonged exposure from field. Irradiance values in W/m2 defined in simulation as heat source depending of an angle of incidence of the sun radiation. At first step, simulation is performing with 5 degree intervals to define the critical zones then intervals decreased to 2 degree to detect the critical azimuth and inclination angles. Critical azimuth and inclination angles is checking with ray trace analysis to check the bouncing of sun rays and possible solution to eliminate focuses with design solutions. After numerical analysis to release and validate the automotive lighting products regarding the sun load test, measurement with first parts is necessary. Measurement is performing for all critical angles which have been detected at simulation with thermal camera under ultra high-collimation solar simulator. Measured temperatures are settled according to environment conditions and correlation is checking with simulations.

A system dynamics simulation model for water conflicts in the Zhanghe River Basin, China

2021 ◽  
pp. 1-17
Author(s):  
Liang Yuan ◽  
Weijun He ◽  
Dagmawi Mulugeta Degefu ◽  
Zhongchi Wan ◽  
Thomas Stephen Ramsey ◽  
...  
Keyword(s):  
System Dynamics ◽  
Simulation Model ◽  
River Basin ◽  
Dynamics Simulation ◽  
Water Conflicts ◽  
System Dynamics Simulation

scholarly journals Macro Modeling of V-Shaped Electro-Thermal MEMS Actuator with Human Error Factor

Micromachines ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 622
Author(s):  
Dongpeng Zhang ◽  
Anjiang Cai ◽  
Yulong Zhao ◽  
Tengjiang Hu
Keyword(s):  
Neural Network ◽  
Simulation Model ◽  
Bp Neural Network ◽  
Human Error ◽  
Calculation Model ◽  
Fuzzy Mathematics ◽  
Ansys Simulation ◽  
Macro Modeling ◽  
Error Factor ◽  
Simulation Results

The V-shaped electro-thermal MEMS actuator model, with the human error factor taken into account, is presented in this paper through the cascading ANSYS simulation model and the Fuzzy mathematics calculation model. The Fuzzy mathematics calculation model introduces the human error factor into the MEMS actuator model by using the BP neural network, which effectively reduces the error between ANSYS simulation results and experimental results to less than 1%. Meanwhile, the V-shaped electro-thermal MEMS actuator model, with the human error factor included, will become more accurate as the database of the V-shaped electro-thermal actuator model grows.

scholarly journals Numerical Investigation for the Resin Filling Behavior during Ultraviolet Nanoimprint Lithography of Subwavelength Moth-Eye Nanostructure

Coatings ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 799
Author(s):  
Yuanchi Cui ◽  
Xuewen Wang ◽  
Chengpeng Zhang ◽  
Jilai Wang ◽  
Zhenyu Shi
Keyword(s):  
Simulation Model ◽  
Nanoimprint Lithography ◽  
Cfd Simulation ◽  
Boundary Slip ◽  
Accurate Analysis ◽  
Inlet Velocity ◽  
Filling Height ◽  
Proposed Model ◽  
Good Consistency ◽  
Computational Fluid Dynamics Cfd

Accurate analysis of the resin filling process into the mold cavity is necessary for the high-precision fabrication of moth-eye nanostructure using the ultraviolet nanoimprint lithography (UV-NIL) technique. In this research, a computational fluid dynamics (CFD) simulation model was proposed to reveal resin filling behavior, in which the effect of boundary slip was considered. By comparison with the experimental results, a good consistency was found, indicating that the simulation model could be used to analyze the resin filling behavior. Based on the proposed model, the effects of process parameters on resin filling behavior were analyzed, including resin viscosity, inlet velocity and resin thickness. It was found that the inlet velocity showed a more significant effect on filling height than the resin viscosity and thickness. Besides, the effects of boundary conditions on resin filling behavior were investigated, and it was found the boundary slip had a significant influence on resin filling behavior, and excellent filling results were obtained with a larger slip velocity on the mold side. This research could provide guidance for a more comprehensive understanding of the resin filling behavior during UV-NIL of subwavelength moth-eye nanostructure.

Mechanical Performance Simulation Model Based on PDM

2013 ◽  
Vol 300-301 ◽  
pp. 32-35
Author(s):  
Xiao Wen Zeng ◽  
Cheng Zeng ◽  
Bing Han
Keyword(s):  
Simulation Model ◽  
Mechanical Performance ◽  
Product Structure ◽  
Dynamics Simulation ◽  
Simulation Data ◽  
Performance Simulation ◽  
Collaborative Simulation ◽  
Complex Simulation ◽  
Mechanical Dynamics ◽  
Relationship Of

In order to manage the complex simulation data management in the process of mechanical dynamics simulation, a new management model was presented which is Performance Simulation Model(PSM). The model was based on PDM product structure and the concepts and elements of PSM were defined in this paper. Furthermore, the functional framework of PSM was proposed which based on the hierarchical relationship of product structure and the data stream relationship of data structure matrix. Finally, PSM was applied on ship planetary reducer collaborative simulation platform. The result indicates that the simulation data in mechanical collaborative simulation are managed by PSM, and the problem of interaction between collaborative simulation and PDM is solved.

Sign in / Sign up

Export Citation Format

Share Document